Schizotypy,cognitive performance,and genetic risk for schizophrenia in a non-clinical population

Schizophrenia risk alleles are expected to mediate effects on cognitive task performance, and aspects of personality including schizotypy, in nonclinical populations. We investigated how 32 of the best-validated schizophrenia risk alleles, singly and as summed genetic risk, were related to measures of schizotypal personality and measures of two aspects of cognitive performance, verbal skills (vocabulary) and visual-spatial skills (mental rotation), in healthy individuals. Summed genetic risk score was not associated with levels of total schizotypy or its three main subscales. Similarly, genotypic variation at none of the individual risk loci was related to cognitive performance measures, after correction for multiple tests. Higher overall genetic risk score was, however, associated with lower performance on the mental rotation test in males, with a broad set of loci contributing to this effect. These results imply that there is a lack of linear, genetically-based continuity connecting schizotypal cognition with the expression of schizophrenia itself, and indicate that, for males, higher genetic risk of schizophrenia exerts negative effects on visual-spatial skills, as measured by mental rotation.     

Relationships between autistic-like and schizotypy traits: An analysis using the Autism Spectrum Quotient and Oxford-Liverpool Inventory of Feelings and Experiences

To further investigate claims of a relationship between autism and schizophrenia, the current study examined the associations between specific dimensions of autistic-like and schizotypy traits. These traits were assessed using the Autism Spectrum Quotient and the Oxford-Liverpool Inventory of Feelings and Experiences. After using factor analysis to explore the dimensions of autistic-like and schizotypy traits represented in these measures in two separate groups of students (N₁ = 362, N₂ = 639), the relationships between these dimensions were examined. While the results are consistent with suggestions in the literature of an overlap in the interpersonal deficits associated with autism and schizophrenia, they offer little support for Crespi and Badcock’s (2008) claim that autism and positive schizophrenia are diametrically opposed disorders.     

The Contributions of Creative Cognition and Schizotypal Symptoms to Creative Achievement

Although previous research has suggested that people with subclinical levels of schizophrenic symptoms achieve a greater number of creative accomplishments, the contention that there is a creative cognitive advantage in schizotypy has received mixed support. It was hypothesized that accounting for complex relationships between (a) creative cognition abilities (moderated relationships), and (b) creative cognition and schizotypy variables (mediated, moderated, and curvilinear relationships) would significantly increase the ability to predict creative performance and provide a more accurate survey of the schizotypic creative cognitive advantage. One hundred and fourteen participants completed a creative problem solving measure, measures of cognitive creative abilities (Remote Associates Test, a divergent thinking task, and a deductive reasoning task) and measures of positive and negative symptoms of schizotypy. Regression analyses supported the conception of a multistage process in which creative cognition variables interact with each other to predict performance on a creative problem solving task. There was no evidence of a creative cognitive advantage in schizotypy: People high in schizotypy performing the same or worse than people reporting few schizotypic symptoms on measures of creative cognition and creative problem solving performance. If people with schizotypy are, indeed, more creative than those without, it is because of factors other than the cognitive processes surveyed in this investigation.     

Are autistic traits autistic?

According to the extreme male brain theory of autism ( Baron‐Cohen, 2002 ), autistic traits would be extreme manifestations of typical male behaviours. The Auyeung et al. (2009) paper establishes a link between autistic traits and higher fetal testosterone (fT) levels in typically developing children. We argue that the construct behind this relationship needs further investigation. First, the link between fT levels and sexually dimorphic traits, that are for example, associated with empathizing and systemizing, is controversial. Likewise, describing autistic behaviours as being extreme male‐like is debatable. The cerebral hemisphere laterality pattern of individuals with autism also seems to differ from the pattern typically observed in males. Moreover, the parallel that should exist, according to the fT theory, between individuals with autism and individuals with congenital adrenal hyperplasia (CAH), because of their high fT levels, is unclear. The theory implying fT levels in autism fails to account for a big part of autism, and the link between fT and normal ‘autistic traits’ hardly demonstrates the causal link between fT and autism.     

Sub‐threshold autism traits: The role of trait emotional intelligence and cognitive flexibility

Theory and research suggests that features of autism are not restricted to individuals diagnosed with autism spectrum disorders (ASDs), and that autism‐like traits vary throughout the general population at lower severities. The present research first investigated the relationship of autism traits with trait emotional intelligence and empathy in a sample of 163 adults aged between 18 and 51 years (44% male). It then examined performance on a set of tasks assessing social cognition and cognitive flexibility in 69 participants with either high or low scores on ASD traits. Results confirm that there is pronounced variation within the general population relating to ASD traits, which reflect similar (though less severe) social‐cognitive and emotional features to those observed in ASDs.     

Understanding constricted affect in schizotypy through computerized prosodic analysis

Constricted affect (CA) is a cardinal negative symptom of schizophrenia-spectrum disorders. It is unclear whether behaviorally-defined CA occurs in individuals with schizotypy-those with the personality organization reflective of schizophrenia liability. Moreover, it is unclear whether CA contributes to real world dysfunction in this population. The present study employed computerized prosodic analysis of natural speech procured during a laboratory procedure. Subjects were 89 individuals with psychometrically-defined schizotypy and 26 controls. Groups did not differ in any of the prosody measures examined here. Within the schizotypy group, increased prosodic expression was associated with positive schizotypy traits while decreased prosodic expression was associated with negative schizotypy traits. Prosodic deficits were significantly associated with reduced prosocial behaviors (e.g., talking with friends) but were not associated with subjective social satisfaction. Prosodic deficits characterize a subset of individuals with schizotypy who show a schizoid-like reduction in social behaviors without a concomitant reduction in social satisfaction.     

Unique sets of social and mood characteristics differentiate autistic and negative schizotypy traits in a young adult non-clinical sample

While well-established as distinct disorders, new evidence linking autism and schizophrenia has emerged. One line of evidence is the strong correlation identified between the social traits assessed by the Autism Spectrum Quotient (AQ:Social) and the negative traits of schizotypy. To further explore this association, the current study examined whether these sets of traits are convergent or divergent in the degree to which they relate to specific aspects of socio-emotional functioning. Regression analyses conducted on self-report data collected from 284 undergraduate students showed that the social items from the AQ uniquely relate to levels of social anxiety and social skills, while negative schizotypy traits uniquely relate to social anhedonia and depression. Additionally, AQ:Social and negative schizotypy traits were found to share a significant proportion of variance, independent of each of the socio-emotional variables examined. The results thus provide further evidence of shared atypical social function linked to both autistic-like traits and negative schizotypy traits, but importantly also highlight clear differences in the specific socio-emotional profiles associated with these sets of traits.     

Schizotypy facets, cognitive control, and emotion

This research examined whether facets of schizotypy were differentially related to cognitive control and emotion-processing traits. In a confirmatory factor analysis (N = 261), a 3-factor model of schizotypy exhibited good fit and fit significantly better than a 2-factor model. In addition, only disorganized schizotypy was associated with poor cognitive control (specifically, prepotent inhibition). Moreover, disorganized but not positive schizotypy was associated with increased emotional confusion and increased emotionality. In contrast, negative schizotypy was associated with increased emotional confusion but decreased emotionality. These results suggest that disorganized schizotypy is related to dysregulation of both cognition and emotion and that negative schizotypy might reflect deficits in the experience and processing of emotion and not just in emotional expression.     

Effects of increasing cognitive load on sustained attention tasks in schizophrenic disorders and schizotypy

In this study we analyze the attentional performance using different cognitive load attentional tasks: low-load cognition (0-CPT) and high-load cognition (DS-CPT). Participants were a group of schizophrenic patients and two groups of normal population psychometrically classified as low schizotypy and high schizotypy according to the SPQ. Our results show that schizophrenic patients were more sensitive to increments on cognitive load, being their attentional performace worse than the rest of the groups. The lack of significant findings in vigilance on the schizotypal traits group is discussed in terms of conceptual and methodological issues about the utility of psychometric strategies to identify vulnerable populations within the spectrum of the schizophrenic disorders.     

Positive schizotypy and emotion processing

This study examined whether emotion processing traits and task performance are associated with positive schizotypy. Positive schizotypy individuals (n=34, assessed with the Magical Ideation and Perceptual Aberration Scales) reported greater attention to emotions but less emotional clarity than controls (n=56). Moreover, a significantly larger percentage of the schizotypy group was classified as emotionally overwhelmed. Positive schizotypy individuals also exhibited absent affective priming and increased incongruent errors at a short stimulus onset asynchrony and an absence of an effect of emotion on recognition memory, but an increased memory response bias for negative words. Results could not be accounted for by level of neuroticism or current mood. These results suggest that positive schizotypy is associated with the processing of emotional information.     

Schizotypal personality traits and attitudes towards Hinduism among Balinese Hindus

The study explored the relationship between schizotypal personality traits and attitude of Hindus towards their faith. A total of 309 Balinese Hindus responded to the Santosh–Francis Scale of Attitude towards Hinduism, the Schizotypal Personality Questionnaire Brief, and a number of external indicators and religious practices. Attitude towards Hinduism, frequency of prayer, and temple attendance had a rather weak positive relationship with each other, while prayer behaviour exhibited negative low-to-moderate relationships with schizotypal traits. A hierarchical multiple linear regression model identified the disorganised elements of schizotypy as the primary predictor of the attitude towards Hinduism. Finally, age showed negative associations with schizotypy and positive ones with Hinduism, while women were less schizotypal and had more positive attitude towards their faith than men. These findings suggest the presence of both underlying cross-faith elements and the strong influence of faith- and culture-specific forces on the relationship between religiosity and schizotypy.     

Taking the Focus Away from the Self: Low Individualism Mediates the Effect of Oxytocin on Creativity

Recently, it has been shown that the hormone oxytocin can enable creative cognition. The aim of this investigation was to examine the psychological mechanism via which oxytocin influences creativity. Two opposing explanatory approaches suggested by previous research were investigated: It was predicted that the effect of oxytocin on creativity would be determined by low versus high individualism, especially in people with low levels of anxiety. Participants filled out an anxiety questionnaire and intranasally administered oxytocin or a placebo. After a 40-min waiting period, they performed a creativity task and indicated their level of individualism. Participants with low levels of anxiety showed heightened creative potential under oxytocin, and this relationship was mediated by low individualism. The results could not be explained by changes in the participants’ affective state. The findings underscore the moderating role of dispositional factors and reveal an important factor to understand the role of oxytocin in human behavior.     

Religious experience,religious orientation and schizotypy

The present study examined the relationship between religious orientation and schizotypy, with the prediction that intrinsic religiosity would be negatively associated with schizotypy, and religious experience and extrinsic religiosity would be positively associated with schizotypy. A total of 308 UK adults (132 men; 176 women) completed measures of religious experience, intrinsic orientation towards religion, extrinsic orientation towards religion, schizotypal personality traits and borderline personality. Though the present findings also suggest that the significant relationships between religiosity and schizotypy traits are fragmented, particularly by sex, the findings are consistent with theory that an intrinsic orientation towards religion is associated with lower levels of schizotypy, and religious experience and an extrinsic orientation towards religion is associated with higher levels of schizotypy.     

Probing Linear and Nonlinear Relations Among Schizotypy,Hypomania, Cognitive Inhibition,and Creativity

This study explored the relationship between schizotypy, hypomania, and indicators of creativity in 152 adult undergraduate students. We were interested in exploring a possible inverted U-shaped relationship between mental illness and creativity where moderate (vs. high or low) amounts of pathology are associated with facilitating creative responses. An indicator of cognitive inhibition derived from Stroop mismatch reaction times was also evaluated as a potential moderating factor between symptomatology and levels of creativity. College students (n = 152) were recruited from an introductory psychology class and completed a series of questionnaires (Schizotypal Personality Questionnaire-BR; Hypomania Checklist-32; Creative Achievement Questionnaire) and experimental tasks (color Stroop task; Wallach-Kogan Creativity Test) with a research assistant in a controlled environment. Polynomial regression results suggested that creative accomplishments were predicted by levels of disorganized schizotypy, but negatively associated with levels of interpersonal schizotypy. Scores on two divergent thinking indices were predicted by levels of disorganized schizotypy, yet surprisingly negatively associated with scores of hypomania. Although the relationship between disorganized symptoms and creative processes was not anticipated, these results may reflect certain nonconforming characteristics (e.g., tendency to wander off the topic in conversations) associated with this symptom domain. Although there was no definitive evidence supporting an inverted-U relationship between symptom severity and creativity within our sample, several linear relationships emerged suggesting that cognitive inhibition acted as a moderator variable for originality in those with higher levels of interpersonal schizotypy. Limitations and recommendations for future research are discussed.     

Handedness, emotional problems, and schizotypy

The purpose of this study was to analyse the relationship between emotional or behavioural problems and schizotypy. An assessment of handedness and schizotypal personality traits were also performed by means of the Thinking and Perceptual Style Questionnaire, the Multidimensional Schizotypal Traits Questionnaire, the Edinburgh Handedness Inventory, and the Youth Self-Report. The sample comprised 296 participants with a mean age of 13.8 and a standard deviation of 1.34. Data indicate that adolescents with high scores on psychometric factors of schizotypy displayed higher patterns of problem behaviours as well as a significant difference in all the core factors of the Youth Self-Report, compared to those who scored low on these measures. Discriminant analysis showed that the core factors of the Youth Self-Report correctly classified 84% of the adolescents with high or low scores on psychometric schizotypy. Lastly, no significant association between the factors of schizotypy and left-handedness, right-handedness, or mixed-handedness was found.     

Personality,creativity and latent inhibition

The current study set out to investigate the relationship between creativity, multi‐dimensional schizotypy and personality more generally. This was achieved by analysing scores on a range of personality scales and measures of creativity, where it was found that the creativity measures were more closely related to asocial‐schizotypy than positive‐schizotypy. The study also sought to test Eysenck's prediction ( 1993 , 1995 ) that, given the putative relationship between creativity and psychosis‐proneness, high psychosis‐prone scoring individuals and high creativity scoring individuals would demonstrate the same cognitive style of ‘overinclusiveness’ on latent inhibition. However, the results failed to demonstrate any evidence of a shared ‘widening of the associative horizon’ between high creativity and high psychosis‐prone scorers. The findings are discussed in relation to multi‐dimensional schizotypy. Copyright © 2006 John Wiley & Sons, Ltd.     

Schizotypy and mental time travel

Mental time travel is the capacity to imagine the autobiographical past and future. Schizotypy is a dimensional measure of psychosis-like traits found to be associated with creativity and imagination. Here, we examine the phenomenological qualities of mental time travel in highly schizotypal individuals. After recollecting past episodes (autobiographical memory) and imagining future events (episodic future thinking), those scoring highly on positive schizotypy reported a greater sense of ‘autonoetic awareness,’ defined as a greater feeling of mental time travel and re-living/‘pre-living’ imagined events. Furthermore, in contrast to other sensory domains, imagery of the past and future episodes contained more olfactory detail in these high scorers. The results are discussed in relation to previous reports of anomalous olfactory experiences in schizotypy and heightened vividness of olfactory imagery in post-traumatic stress disorder, for which schizotypy is a risk factor.     

Schizotypy and mental health amongst poets, visual artists, and mathematicians

Many researchers have found evidence of an association between creativity and the predisposition to mental illness. However, a number of questions remain unanswered. First, it is not clear whether healthy creatives have a milder loading on schizotypal traits than people who suffer serious psychopathology, or whether they have an equal loading, but other mediating characteristics. Second, most of the existing research has concentrated on artistic creativity, and the position of other creative domains is not yet clear. The present study compares schizotypy profiles using the O-LIFE inventory in a large sample of poets, artists, mathematicians, the general population, and psychiatric patients. Poets and artists have levels of unusual experiences that are higher than controls, and as high as schizophrenia patients. However, they are relatively low on the dimension of introvertive anhedonia. Mathematicians are lower than controls on unusual experiences. The results suggest that artistic creatives and psychiatric patients share a tendency to unusual ideas and experiences, but creative groups are distinguished by the absence of anhedonia and avolition. Moreover, different domains of creativity require different cognitive profiles, with poetry and art associated with divergent thinking, schizophrenia and affective disorder, and mathematics associated with convergent thinking and autism.     

Investigating the interaction between schizotypy, divergent thinking and cannabis use

Cannabis acutely increases schizotypy and chronic use is associated with elevated rates of psychosis. Creative individuals have higher levels of schizotypy, however links between cannabis use, schizotypy and creativity have not been investigated. We investigated the effects of cannabis smoked naturalistically on schizotypy and divergent thinking, a measure of creativity. One hundred and sixty cannabis users were tested on 1 day when sober and another day when intoxicated with cannabis. State and trait measures of both schizotypy and creativity were administered. Quartile splits compared those lowest (n=47) and highest (n=43) in trait creativity. Cannabis increased verbal fluency in low creatives to the same level as that of high creatives. Cannabis increased state psychosis-like symptoms in both groups and the high creativity group were significantly higher in trait schizotypy, but this does not appear to be linked to the verbal fluency change. Acute cannabis use increases divergent thinking as indexed by verbal fluency in low creatives.